Emma Navarro’s RED-S account shows how strong results coexisted with poor health, and why persistent symptoms deserve professional assessment.
Emma Navarro said she was ending her 2026 season to focus on her health. In its reporting on her account, The Athletic described how major competitive achievements had coincided with persistent physical and mental difficulties. Navarro said she received a diagnosis of relative energy deficiency in sport, or RED-S, in fall 2025 and also reported Hashimoto’s hypothyroidism.
Her account offers an important distinction for endurance athletes over 35: performing well and feeling well are not necessarily the same thing. Continued progress is worth celebrating. It is not a reason to dismiss health problems that keep returning.
The Athletic reported that Navarro climbed from world No. 149 to No. 8 in about 20 months. It also reported that she played more singles matches than nearly all her peers for two consecutive years.
Those achievements formed the backdrop to a very different personal experience. Navarro said her health difficulties began around 2023 as her professional career accelerated. She linked them to choices involving training, fueling, competition and recovery.
According to her account as reported by The Athletic, her difficulties included:
The significance is not that a successful athlete sometimes felt tired. It is that a sustained competitive rise occurred alongside problems affecting several parts of her life. Looking only at rankings would have missed much of that experience.
Navarro said she changed her fueling and addressed her hypothyroidism. She reported more consistent sleep, less dizziness and fewer headaches afterward. Later, she described feeling more comfortable in the gym and noticing improvements in cognitive function and mental bandwidth.
That last detail matters beyond sport. Training discussions often center on whether an athlete can complete a session or deliver a result. Navarro’s account also concerned how she slept, thought and felt outside competition.
For an ambitious athlete, those experiences deserve a place in the conversation about progress. The ability to keep training does not make every other difficulty irrelevant.
Registered dietitian and physiologist Anna Roby told The Athletic that RED-S can affect athletes regardless of gender, sport or body type. She also cautioned against assuming that intentional food restriction must be involved. An athlete may misjudge training demands or fueling needs.
That distinction changes the conversation. The relevant question is not simply whether someone believes they eat well or is deliberately trying to eat less. It is whether fueling fits the demands being placed on the athlete.
Emily Kraus, director of Stanford’s Female Athlete Science and Translational Research program, told The Athletic that athletes may mistake RED-S symptoms for normal effects of high performance. She warned that treating symptoms separately can obscure a broader fueling problem.
Taken together, those observations support looking at the whole picture rather than relying on a particular appearance or an explanation for each complaint.
The Athletic reported that Navarro declined an interview and preferred to let her social-media account stand. Her symptoms and improvements should therefore be understood as her own account rather than independently verified clinical findings. The experts quoted in the report were not discussing her case directly.
Navarro also reported Hashimoto’s hypothyroidism and described addressing it alongside changes to fueling. Her experience does not establish that RED-S caused every symptom or identify which change produced each improvement. It is an elite tennis player’s account rather than a controlled study of adult recreational endurance athletes.
Fatigue, disrupted sleep and recurring illness can also have other medical causes. The practical response to a persistent pattern is professional assessment rather than assigning a diagnosis from a symptom list.
For a veteran runner, cyclist or triathlete, the useful translation is about what deserves attention. A demanding session may dominate the training diary while changes in everyday well-being receive only a passing mention. Navarro’s account is a reason to give those observations room.
The question is not whether an amateur training schedule resembles a professional tennis season. It is whether ongoing difficulties are being accepted simply because training and racing continue.
If symptoms are accumulating, a conversation with a qualified clinician can include more than the most recent complaint. The practical aim is to describe what has changed and how it fits with training and daily life.
Useful information to bring includes:
This is preparation for a conversation, not a home screening test. It gives the clinician a clearer account of the circumstances in which problems developed.
Kraus told The Athletic that clinicians and an athlete’s support network can help connect symptoms. She included coaches, athletic trainers and performance staff among those who can raise questions about fueling and recovery between demanding efforts.
For an athlete who works with a coach, that supports sharing relevant concerns rather than discussing only pace or power. The coach can contribute context about training demands while medical questions remain with qualified healthcare professionals.
Roby’s comments make room for an important possibility: someone can be committed to training and still misunderstand what that training requires from fueling. That is a practical issue to discuss without turning it into a judgment about discipline or character.
Questions about which nutrition details deserve attention belong in that broader conversation. The goal is to make relevant information available to the people assessing the problem. Collecting more information is useful only when it helps clarify the situation.
Navarro’s account also places recovery alongside fueling and competition. For endurance athletes, those topics are better discussed together than treated as unrelated parts of the training week.
That does not require adopting another athlete’s menu or copying changes described on social media. It means making fueling and recovery visible when explaining the demands of training and the difficulties occurring around it.
Nothing in Navarro’s account requires endurance athletes to become less ambitious. It does challenge the idea that continued success settles questions about health.
An athlete can value race results while also taking persistent hunger, disrupted sleep or reduced well-being seriously. Those priorities need not compete. Asking for help is compatible with wanting to improve.
This fits a broader discussion of how to judge progress after 35. Performance can remain an important measure without becoming the only measure that earns attention.
A useful question is whether the explanation being offered accounts for the whole experience. “Training is hard” may describe the workload. It should not automatically end a conversation about recurring health problems.
Navarro’s account brings a difficult mismatch into view: she continued reaching major competitive milestones while feeling physically and mentally unwell. She later reported improvements after changing her fueling and addressing a thyroid condition.
For endurance athletes over 35, the grounded takeaway is to give persistent changes in well-being a place alongside training data and race results. Describe the pattern to a qualified clinician and include the context of fueling, competition and recovery.
There is no need to wait for performance to collapse before a health concern deserves attention. Taking that concern seriously is consistent with staying ambitious for the long term.
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